Any under-discovered/under appreciated Scandinavian rock/metal bands? ?

Not Scandinavian but Baltic and slavic. 

Lithuanian - Thundertale (hard rock), Gyvata (folk/pagan rock), Juodvarnis (black metal) and Wolfsome (sound similar to Black Keys.) 

Skyforger (Latvian). 

Helroth and Percival Schuttenbach (Polish)

How about some Kent or is this too soft? They are very popular in Sweden, but probably not all that well known outside of Sweden.

Kent - Kärleken väntar

https://www.youtube.com/watch?v=5TMVhSEZeOI

Or this old classic?

Mikael Rickfors - Vingar

https://www.youtube.com/watch?v=zCAoybt4qAo

Another classic... Once again, too soft? I'm not really into rock. =)

Tomas Ledin - Just nu

https://www.youtube.com/watch?v=tie3yuAxjVc

A few off the beaten path

Dawn Of Solace (Finland)

Frantic Amber (Sweden)

The Man-Eating Tree (Finland)

Mors Subita (Finland)

Solution .45 (Sweden)

The Arcane Order (Denmark)

This Ending (Sweden)

Tracedawn (Finland)

Vagrant God (Norway)

Without Grief (Sweden)

I don't consider any of the Scandinavian music I listen to to be undiscovered, it's all fairly well known within the scene, but there isn't really any such thing as "mainstream" metal, as in getting radio play and such.

Ihsahn, Leprous, Shining(NOR), Borknagar, Enslaved, Amorphis, Ensiferum, Stam1na, Meshuggah, Opeth, Soilwork, Edge of Sanity, At the Gates, Dimmu Borgir(actually this band got very popular)

Would Swedish do ? I am half Swede ya know. I am with Dominique on the FACT Danes ARE Scandinavian.

Please try (I like their oldest stuff better, the second link I provide)

https://www.youtube.com/watch?v=KYjtBBeweu4

https://www.youtube.com/watch?v=OmbKpxvf0rg

and to ALL a good night

GOOD NIGHT

The Raveonettes might fit that description.